Mixing coefficients for d orbitals in copper(II) complexes with lower symmetry. Part 2.—Ionic radii of copper(II) ions in complexes

Abstract

The ionic radii of low-symmetry copper(II) compounds have been investigated in the xy plane and are shown to be reasonably represented by linear equations. The theoretical expression is ri=K(r)i〈ψ21〉/E|(z2)〉+r0i(i=x, y). When evaluated for six compounds whose structure is known this becomes ry/A= 1.00556(a1–b1/[graphic omitted])2/E|(z2)〉+ 0.6706 and rx/A= 0.5832(–a1–b1/[graphic omitted])2/|(z2)〉+ 0.6787, where a1 and b1 are the mixing coefficients of the dx2–y2 and dz2 orbitals in the ground-state wavefunction, and E|(z2)〉 is the energy of the 2Ag|(Z2)〉â†�2Ag|(X2–Y2)〉 transition in kK. The values for the mixing coefficients a1 and b1 can be calculated for compounds of copper(II) if the radii and E|(z2)〉 are known. The least-squares equations for all compounds are ry/A= 1.0464/E|(z2)〉+ 0.6706 and rx/A= 0.4446/E|(z2)〉+ 0.6787. The average error is ca. 3–4%. An equation was also developed for the average radius in the xy plane.